Ts Value Research Articles

Antibacterial, cytotoxic and mechanical properties of a orthodontic cement with phosphate nano-sized and phosphorylated chitosan: An in vitro study

ObjectivesEvaluate, in vitro, the effect of incorporating nano-sized sodium trimetaphosphate (TMPnano) and phosphorylated chitosan (Chi-Ph) into resin-modified glass ionomer cement (RMGIC) used for orthodontic bracket cementation, on mechanical, fluoride release, antimicrobial and cytotoxic properties. MethodsRMGIC was combined with Chi-Ph (0.25%/0.5%) and/or TMPnano (14%). The diametral compressive/tensile strength (DCS/TS), surface hardness (SH) and degree of conversion (%DC) were determined. For fluoride (F) release, samples were immersed in des/remineralizing solutions. Antimicrobial/antibiofilm activity was evaluated by the agar diffusion test and biofilm metabolism (XTT). Cytotoxicity in fibroblasts was assessed with the resazurin method. ResultsAfter 24 h, the RMGIC-14%TMPnano group showed a lower TS value (p < 0.001); after 7 days the RMGIC-14%TMPnano-0.25%Chi-Ph group showed the highest value (p < 0.001). For DCS, the RMGIC group (24 h) showed the highest value (p < 0.001); after 7 days, the highest value was observed for the RMGIC-14%TMPnano-0.25%Chi-Ph (p < 0.001). RMGIC-14%TMPnano, RMGIC-14%TMPnano-0.25%Chi-Ph, RMGIC-14%TMPnano-0.5%Chi-Ph showed higher and similar release of F (p > 0.001). In the SH, the RMGIC-0.25%Chi-Ph; RMGIC-0.5%Chi-Ph; RMGIC-14%TMPnano-0.5%Chi-Ph groups showed similar results after 7 days (p > 0.001). The RMGIC-14%TMPnano-0.25%Chi-Ph group showed a better effect on microbial/antibiofilm growth, and the highest efficacy on cell viability (p < 0.001). After 72 h, only the RMGIC-14%TMPnano-0.25%Chi-Ph group showed cell viability (p < 0.001). ConclusionThe RMGIC-14%TMPnano-0.25%Chi-Ph did not alter the physical-mechanical properties, was not toxic to fibroblasts and reduced the viability and metabolism of S. mutans. Clinical relevanceThe addition of phosphorylated chitosan and organic phosphate to RMGIC could provide an antibiofilm and remineralizing effect on the tooth enamel of orthodontic patients, who are prone to a high cariogenic challenge due to fluctuations in oral pH and progression of carious lesions.

Optimizing the Return Vent Height for Improved Performance in Stratified Air Distribution Systems

One of the factors that strongly impacts the efficacy of stratified air distribution (STRAD) systems is the return vent height (H), for which different studies have yielded different suggested values. This theoretical research uses a displacement ventilation (DV) system as an example to examine how the H affects the efficacy of STRAD systems through analysis of the trade-offs between the cost of the vertical temperature gradient and the benefits of energy reduction. The key results are as follows: (a) The energy savings due to a lower H are smaller than the cost of the vertical temperature gradient for all STRAD systems. (b) With a supply temperature (Ts) set at 18 °C, elevated return vent positions can result in excessively cooled areas, while extremely low vent positions create a temperature gradient exceeding 3 °C between the head and ankles. (c) The TOPSIS methodology reveals that the optimal H value lies in the range of 1.5–2.3 m when Ts is 18 °C. (d) When adjusting the Ts value to achieve thermal neutrality, 2.3 m is identified as the optimal H value, demonstrating superior performance over the 1.5 m to 2.3 m range at 18 °C Ts. These findings highlight the benefit of a higher H for STRAD systems and the significance of configuring ventilation systems for thermal neutrality.

Simple and low-cost anion exchange membrane based on PVA and PDC for acid recovery by diffusion dialysis

Anion exchange membranes were prepared by a simple method on the basis of polyvinyl alcohol (PVA) and 1,4-Piperazinedicarboxaldehyde (PDC). A network structure was formed in the membranes by cross-linking between PVA and PDC. The mechanical stability and acid stability the prepared membranes was tested. The TS value was tested as 17.5–37.8 MPa, Eb was 120.4–54.7% and the mass retention in the acid environment was 98.4–97.2%. Meanwhile, the physicochemical properties of membranes, such as thermogravimetric analysis (TGA), water absorption (WR), ion exchange capacity (IEC) and linear expansion rate (LER). WR was 106.9–136.7%, IEC was 1.03–1.55 mmol/g, and LER was 37.93–33.33%. In practical application, diffusion dialysis (DD) performance of membranes were tested. In DD test, the acid dialysis coefficient (UH+) was 17.5–27.9 × 10−3 m/h, and the separation factor (S) was 31.25–23.38. The UH+ and S were all higher than commercial membrane DF-120 (UH+ is 9 × 10−3 m/h and S is 18.00). Results were shown that the comprehensive properties of membranes were good. Therefore, the prepared membranes had broad application prospects for acid recovery by diffusion dialysis.

The slip tendency of 3D faults in Germany

Abstract. Fault reactivation potential is a crucial aspect for many underground utilizations, such as the construction and long-term safety of a nuclear waste repository, as seismic events can endanger these operations. An estimation of the fault reactivation potential requires information about the stress field, but stress data are only available pointwise and are not evenly distributed throughout Germany. Geomechanical–numerical modeling can be used to derive a spatially continuous description of all six independent components of the stress tensor as shown by the model of Germany by Ahlers et al. (2022). Information about the geometry of faults extending several kilometers in depth is provided for most areas in Germany by the geological models of the federal states and geological models created in the framework of projects such as GeoMol (Assessing subsurface potentials of the Alpine Foreland Basins for sustainable planning and use of natural resources) or GeORG (Geopotenziale des tieferen Untergrundes im Oberrheingraben). We use the 3D fault geometries provided by such models and map the stress data from the Germany model by Ahlers et al. (2022) onto these faults. Then, assuming hydrostatic pore pressure, we calculate the so-called slip tendency (TS), the ratio between resolved shear stress and the effective normal stress on the fault plane as a measure of fault reactivation potential. A fault is considered critical when its TS value exceeds its coefficient of friction. In general, TS ranges between 0 and 0.7 for the analyzed faults. The highest overall TS values are observed along the NNE–SSW-striking Upper Rhine Graben, where TS routinely reaches and exceeds values of 0.7. In the North German Basin, the Ore Mountains and Saxony only very few TS values exceed 0.7. The area with the lowest overall TS is the Molasse Basin, where the TS of the mostly WSW–ENE-striking faults only rarely exceeds values of 0.4. In general, N–S- to NNE–SSW- and NW–SE-striking faults show the highest TS values, whereas WSW–ENE-striking faults show the overall lowest values. With increasing depth, TS decreases. Pore pressure and overpressure have the potential to significantly influence the resulting TS.

Electrically actuated characteristics and electrochemical mechanism of a flexible biomimetic artificial muscle regulated by the responsive polymer of the calcium alginate gelation

In comparison to conventional actuated techniques, the utilization of a Flexible Biomimetic Artificial Muscle (FBAM) incorporating calcium alginate hydrogel, a type of responsive polymer, offers numerous benefits including reduced weight, lower actuated voltage requirements, enhanced specific energy density, and minimal acoustic disturbances, among others. This paper presents the fabrication of the FBAM through calcium alginate gelation utilizing six calcium salts with identical Ca2+ molar mass. Subsequently, the electrically actuated characteristics and electrochemical mechanism of the FBAM were investigated, employing four evaluation indexes: peak force density (D, mN/g), operating life (Tt, s), response speed (Vr, mN/g·s), and rise time (Ts, s). The findings of this study hold significant implications for the advancement of novel responsive polymers for artificial muscles. The findings of the study indicate that the electrically actuated characteristics of FBAM were most optimal when calcium alginate gelation with CaH8I2O4 was employed. This was evidenced by the D value of 22.807 mN/g, Tt value of 1066 s, Vr value of 98 s, and Ts value of 0.1046 mN/g·s. The sufficient degree of calcium alginate gelation between sodium alginate molecule and Ca2+ cations resulted in the formation of intermolecular bridges within the calcium alginate hydrogel, which consisted of polymer β-D-mannuronic and α-L-guluronic. Notably, this gelation process was found to be inversely related to the pH level in the aqueous solution of the electrically actuated membrane.

Evaluation of appropriate conditions for Oncomine DxTT testing of FFPE specimens for driver gene alterations in non-small cell lung cancer.

The Oncomine Dx Target Test Multi-CDx System (ODxTT) is a next-generation sequencing panel approved as a companion diagnostic for drugs targeted to corresponding gene alterations in non-small cell lung cancer. However, appropriate slide conditions for ODxTT have remained unclear. We focused on the production of the number of tumor cells on a formalin-fixed paraffin-embedded (FFPE) section and the number of prepared slides, designated the TS value, and determined a TS value of ≥4000 as a target slide condition for ODxTT. We evaluated the impact of this condition on ODxTT testing with tumor specimens found to have a TS of <4000 (n = 23) or a TS of ≥4000 (n = 142). A positive correlation was apparent between the TS value and the concentrations of both DNA and RNA. Among the 142 samples with a TS of ≥4000, a sufficient concentration of DNA or RNA for ODxTT analysis was achieved in 100% and 98% samples, respectively. Among samples explored for driver gene alterations after determination of the target slide condition (TS ≥4000), most (84.9%) had a TS of ≥4000 and were submitted for ODxTT analysis. Our findings indicate that a TS of ≥4000 is a feasible and relevant criterion for ODxTT testing, and its adoption should help to improve the success rate of such testing in clinical practice.

The effects of aspect ratio of cellulose nanocrystals on the properties of all CNC films: Tunicate and wood CNCs

In this study, the physicochemical, mechanical, and thermal properties of films made from cellulose nanocrystals (CNCs) obtained from two sources – wood and tunicate - and their hybrids were investigated. It was found that different morphologies affect the properties of CNC films. Specifically, the surface morphology of tunicate CNC (TCNC) films differed significantly from wood CNC (WCNC) films, and the structure of hybrid CNC (HCNC) films was also different. Compared to wood CNC-containing films, tunicate CNC films exhibited significantly higher BET surface areas, superior thermal properties, greater surface roughness, and very low (≈1 wt.%) dispersibility in water due to their ability to form long-range connectivity. The average BET surface area of TCNC films was measured at 91.9 ± 2.1 m2/g, and this value decreased with the addition of WCNCs to the film structure. The pore diameter also decreased from 11.362 nm for TCNC films to 0.437 nm for WCNC films, indicating the filler effect of WCNCs on the TCNC films. The chiral nematic phase exhibited by WCNC films was confirmed by their iridescent appearance, as observed through cross-sectional SEM images. The TS for TCNC and HCNC3 was measured at 185.2 ± 10.5 MPa and 182.9 ± 13.7 MPa, respectively, which were the highest values among the samples. The lowest TS value of 113.1 ± 9.5 MPa was observed in the WCNC films. A similar decline was observed in the EB values, from 1.76 ± 0.37% for TCNC to 0.9 ± 0.22% for WCNC. This study provides information and knowledge useful for understanding the impact of biomass source on the properties of CNC films for a variety of purposes, including packaging materials, biodegradable coatings, flexible electronics, and membrane applications.

Target strength of seahorse (Hippocampus kuda) based on presence dorsal and ventral aspect of brood pouch: a experiment hydroacoustic using artificial neural network

Hydroacoustic technology is a tool can be used to study the behavior of organisms. The target strength of an object is main key in hydroacoustic technology. The value of target strength is strongly influenced by level of hardness of object, in this case the seahorse has a different level of hardness between dorsal and ventral aspect. The unique of male seahorse that experiences pregnancy and keeps it’s baby in brood pouch until it hatches. This can be used as a difference between males and females based on value of target strength. Acoustic data recording using single beam scientific echosounder SIMRAD EK-15 and Sonar-4 processing software. The results showed that mean TS value of pregnant male seahorses (with brood pouch) was smaller than of female seahorses (without brood pouch), there were differences in structure composition and anatomy of the brood pouch which backscattering strength to decrease. The artificial neural network shows that there is a difference in response between seahorse (having a brood pouch/male) compared seahorse (without a brood pouch/female). The results showed that was a difference in dorsal aspect of 87.5% and ventral aspect of 98.6%. The results of this study can be used as key to distinguish sex of seahorses using the hydroacoustic method.

Effect of Substrate Temperature on Photoelectric Properties of AZO Thin Films

Herein, Al‐doped ZnO (AZO) thin films are prepared on quartz glass substrates by RF magnetron sputtering. The effects of substrate temperature (T s) on the structure, morphology, electrical, and optical properties of AZO films are investigated by X‐ray diffraction, field emission electron microscopy, Hall effect testing instrument, and ultraviolet spectrophotometer, respectively. The results show that the doping of Al element does not change the structure of ZnO films, and all films have typical hexagonal wurtzite structure with preferred c‐axis orientation. The film sample has the strongest (002) diffraction peak and the smallest value of full‐width at half‐maximum at the T s value of 150 °C. With the increase of T s value, the grain size of the film increases first and then decreases. At 150 °C, the film exhibits good electrical conductivity, and its resistivity is 0.6210−2 Ω cm, the carrier concentration is 9.841019 cm−3, and the Hall mobility is 13.66 cm2 V−1 s−1. All samples show high transmittance, and the average transmittance in the stable visible light region is as high as 95% at the T s value of room temperature and 250 °C, and the average transmittance of all samples is above 80%. This provides a method for the application of ZnO transparent conductive films.

Effects of various operating conditions and optimal ionomer-gradient distribution on temperature-driven water transport in cathode catalyst layer of PEMFC

Temperature distribution affects water transport by phase-change-induced (PCI) flow in the cathode catalyst layer, where water generates and heat releases. To elucidate the role of PCI flow in water removal, a 1-D, non-isothermal, two-phase model coupled with an agglomerate submodel is established and a dimensionless parameter, Ts, evaluating the relation between the capillary-driven flow and PCI flow is also employed. The effects of operating temperature and inlet relative humidity (RH) on the Ts value are investigated in detail. The results show that raising the operating temperature (from 333.15 K to 363.15 K) contributes to increased Ts and extension of the PCI flow dominating area. Compared with other RH cases, Case-D has the highest Ts due to the adsorption/desorption process between equilibrium water content and dissolved water content as well as the changes of phase-change heat in the cathode catalyst layer. But the widest PCI flow dominating area emerges at Case-C. Lastly, the well-designed ionomer-gradient distribution is identified by the Particle Swarm Optimization algorithm, namely reduction along the through-plane direction in the cathode catalyst layer with three sub-layers, which in turn increases the local porosity. As a result, the overall mass transport capability is enhanced, as reflected by the decrease of Damkohler number and increase of effectiveness factor, thus promoting the output performance. Also, this optimization facilitates the PCI flow and expands the PCI flow dominating area. Overall, it is realizable to avoid water flooding by reasonably adjusting the operating conditions as well as optimizing the catalyst layer gradient structure.

Validating the Impact of Water Potential and Temperature on Seed Germination of Wheat (Triticum aestivum L.) via Hydrothermal Time Model.

Wheat is the most extensively cultivated crop and occupies a central place in human nutrition providing 20% of the daily food calories. This study was conducted to find both T and ψ effects on wheat germination and the cardinal Ts value; a lab experiment was accomplished using HTT models. Cultivars were germinated under different accelerated aging periods (AAP, 0, 24, 48, and 72 h) at each of the following constant Ts of 15, 20, 25, 30, and 35 °C at each of the ψs of 0, −0.05, −0.1, −0.15, and −0.2 MPa. GR, GP, and other germination parameters (GI, GRI, CVG, SVI-I, SVI-II, GE, and MGT) were significantly determined by solute potential, temperature, and reciprocal action in both cultivars (p ≤ 0.01). Depending on the confidence interval of the model co-efficiently between cultivars, there was no significant difference. Hence, the average of cardinal Ts was 15, 20, and 35 °C for the Tb, To, and Tc, respectively, in the control condition (0 MPa). Hydro-time values declined when Ts was raised to To in cultivars, then remained constant at Ts ≥ To (2.4 MPah−1 in Pirsabak 15 and 0.96 MPah−1 in Shahkar). The slope of the relationship between ψb(50) and TTsupra with temperature when Ts is raised above To and reaches 0 at Tc. In conclusion, the assessed parameter values in this study can easily be used in simulation models of wheat germination to quantitatively characterize the physiological status of wheat seed populations at different Ts and ψs.

Using the hydroacoustic and mini trawl data for estimating fish density in the eastern part of Banyuasin coastal waters, South Sumatra of Indonesia

The hydroacoustic and mini trawl sampling was conducted to estimate a distribution pattern of fish density in the eastern part of Banyuasin coastal waters, South Sumatra, Indonesia. These surveys were carried out in September 2017 using a SIMRAD EK15 single‐beam echo sounder with a 200 kHz operating frequency. Catch data obtained from the mini bottom trawl were used to examine a dominant species for refining the TS value concerning the fish density estimation along the hydroacoustic track. The ponyfishes (Eubleekeria jonesi) from the Leiognathidae family were found at each station with the highest relative abundance (50.98%). Hence this species was used to refine target strength values for estimating the acoustic volume density. These volume densities of 206 ESDU ranged from 0 to 9048 fish 1000m–3, with an average of 930 fish 1000m–3. The results also described a distribution pattern of fish densities hence this information could be valuable to the fishery manager for improving sustainable management approaches.

Measurement and Analysis of Target Strength of Tiger Grouper Fish (Epinephelus fuscoguttatus) Using Acoustic Methods in Lancang Island Seawater

Coral fish are organisms with the largest amount of biomass and are also large organisms that can be found in coral reef ecosystems. The tendency of coral fish is that they do not move around and are always in a certain area and are very relocated although still many (Nybakken, 1988). The coral fish that are often found on the island of Lancang is the Tiger Grouper fish (Epinepheus fuscoguttatus). Grouper fish have a high economic value if fishermen do good cultivation on this Lancang island. The method used was mobile and controlled hydroacoustics, located in Pulu Lancang Thousand Islands. The instruments used are SIMRAD EK 15. The number of samples measured as many as 3 heads with a total length ranging from 21,70 cm to 42,50 cm and has the total weight of the three fish of 186,9 gr to 640 gr with a recording time of 5 minutes was done at the Dock and Floating Net Cage. The sounding results of tiger grouper were then analyzed using Echoview 4.0 and microsoft excel. The results of the analysis showed the average TS value in 3 tiger groupers whose total length ranged from -34,77 dB to -32,37 dB and the longer the total length of the fish, the greater the TS value.

Testing a maximum evaporation theory over saturated land: implications for potential evaporation estimation

Abstract. State-of-the-art evaporation models usually assume net radiation (Rn) and surface temperature (Ts; or near-surface air temperature) to be independent forcings on evaporation. However, Rn depends directly on Ts via outgoing longwave radiation, and this creates a physical coupling between Rn and Ts that extends to evaporation. In this study, we test a maximum evaporation theory originally developed for the global ocean over saturated land surfaces, which explicitly acknowledges the interactions between radiation, Ts, and evaporation. Similar to the ocean surface, we find that a maximum evaporation (LEmax) emerges over saturated land that represents a generic trade-off between a lower Rn and a higher evaporation fraction as Ts increases. Compared with flux site observations at the daily scale, we show that LEmax corresponds well to observed evaporation under non-water-limited conditions and that the Ts value at which LEmax occurs also corresponds with the observed Ts. Our results suggest that saturated land surfaces behave essentially the same as ocean surfaces at timescales longer than a day and further imply that the maximum evaporation concept is a natural attribute of saturated land surfaces, which can be the basis of a new approach to estimating evaporation.

Effect of Shape, Orientation and Aging of a Plastic Greenhouse Cover on the Degradation Rate of the Optical Properties in Arid Climates

In arid climates, the optical properties of plastic-covered greenhouses deteriorate very quickly. To examine the effect of greenhouse shape and orientation on the degradation rate of cover optical properties, four greenhouse prototypes were constructed in two shapes (duo-pitched roof and tunnel), covered with a 200 µm thick low-density polyethylene film. Two types were oriented in the North–South direction, the other two in the East–West direction, and all were exposed for one year to an arid climate. Samples were taken from the different surfaces of each cover for testing. The total transmittance (Ts) and reflectance (Rs) of the samples were measured and averaged to obtain the whole cover properties (T and R). Measurements were carried out periodically every 30 days for the four prototypes. The degradation behavior of the optical properties of each cover surface (Ts, Rs) and the whole cover (T, R) was investigated for the four film covers during the exposure time. Results show that the degradation rate of Ts depends on the surface location and the cover orientation. Among the different surfaces of the four prototype covers, the maximum difference in the Ts value between the E and N surfaces for the tunnel cover oriented in the N–S direction was 15.5%. Although the variation of the Ts value among the different cover surfaces was found, the time dependences of the whole cover transmittance (T) for the four covers tested were almost similar. Accordingly, the shape and orientation of the small size greenhouses did not significantly affect the degradation rate of the cover optical properties. In the four covers tested, the reduction in the global solar radiation transmittance (T) was 27–31% after one-year exposure compared to the new film. Nonlinear correlation was developed to predict the degradation rate of the cover transmittance as a function of the accumulated solar irradiance.

Is TOL 1326–379 a Prototype of γ-Ray Emitting FR0 Radio Galaxy?

With the possible spacial association to the Fermi/LAT source 3FGL J1330.0–3818, TOL 1326–379 may be the first one that is identified as a γ-ray emitting Fanaroff–Riley type 0 radio galaxy (FR0 RG). We analyze the ∼12 yr Fermi/LAT observation data of this γ-ray source and examine its association to TOL 1326–379. We show that the γ-ray source (named as J1331.0–3818) is tentatively detected with a TS value of 28.7, 3FGL J1330.0–3818 is out of the 95% containment of J1331.0–3818, and their positions are spatially separated ∼0.°2. 4FGL J1331.3–3818 falls into the 68% containment of J1331.0–3818, suggesting that our result agrees with that reported in the Fourth Fermi LAT Source Catalog. TOL 1326–379 is out of the 95% containment of J1331.0–3818, and their positions are spatially separated ∼0.°4, indicating that the association between J1331.0–3818 and TOL 1326–379 is quite ambiguous. However, we do not find other possible potential radio or X-ray counterpart within the circle centered at J1331.0–3818 with a radius of 0.°4. The spectral energy distribution (SED) of TOL 1326–379 shows a bimodal feature as seen in the γ-ray emitting RGs. We fit the SED with the one-zone leptonic model and find that the average energy spectrum of J1331.0–3818 agrees with the model prediction. Assuming that J1331.0–3818 is an unidentified γ-ray source, we derive the upper-limit of the γ-ray flux for TOL 1326–379. It is not tight enough to exclude this possibility with the SED modeling. Based on these results, we cautiously argue that the γ-ray source J1331.0–3818 is associated with TOL 1326–379 and its jet radiation physic is similar to those γ-ray emitting RGs.

Kajian Hambur Balik Akustik Dari Tukik Penyu Lekang (Lepidochelys olivacea) Melalui Pengukuran Secara Terkontrol Pada Frekuensi 200 kHz

Turtles are marine reptiles that are protected because of their endangered population. The Convention on International Trade in Endangered of Wild Flora and Fauna (CITES) stipulates seven species of sea turtles in the world into Appendix I as endangered, protected and not exploited in any form. The number of hatchlings that managed to reach the sea is currently difficult to know, one method that can be used to detect the presence of hatchlings in nature is by using the acoustic method. This study aims to analyze the backscatter characteristics of the turtle hatchlings and to determine the relationship between backscattering and body length of the turtle hatchlings. The benefits of this research are expected to be able to provide information about the value of backscatter and the relationship to the body length of hatchlings that can be used as a basis for estimating the stock or abundance of hatchlings in nature. This research was conducted in the waters of the Tapak Padri pond, Bengkulu City. The research implementation takes about 3 months, from August to October 2020. Acoustic data processing is carried out at the Marine Acoustic and Resource Exploration Laboratory, Marine Department, FMIPA, Sriwijaya University, Palembang. The results obtained are that the average value of TS ranges from -52.74 to -48.45 dB for hatchlings length of 7-9.3 cm. Based on the regression equation, the coefficient of determination (R2) obtained is 0.57, so it is known that the total length affects the target strength value by 57% and 43% is influenced by other factors. it can be concluded that there is a relationship between the total length of the hatchlings with the TS value of the hatchlings or the total length has an influence on the magnitude of the TS value in the hatchlings.

Search for gamma-ray emission from the 12 nearby dwarf spheroidal galaxies with 12 years of Fermi-LAT data

Previously, we have shown in Li et al. (2018) that very weak $\gamma$-ray excesses ($\sim 2\sigma$) appear in some Milky Way dwarf spheroidal galaxies (dSphs, including candidates) and the combination analysis of 12 nearby dSphs yields a local significance of $>4\sigma$. In this work, we adopt a longer data set (i.e., the 12 years of Fermi-LAT data), the latest Fermi-LAT software as well as background models to update the searches of $\gamma$-ray emission from these sources. Very weak $\gamma$-ray excesses ($>$ 2 $\sigma$) are found in the directions of three dSphs, including Reticulum II, Bootes II and Willman 1. In the direction of Reticulum II, the peak TS value of the excess reaches $\sim$11. However, different from the previous analysis with the 9 years of Fermi-LAT data, now the location of the gamma-ray emission is significantly away from the center of Reticulum II because of the enhancement of "offset" $\gamma$-rays above 10 GeV since 2017. The detected weak excess is likely due to the contamination of an astrophysical $\gamma$-ray source with a TS value of $\sim 22$, irrelevant to the dark matter inside Reticulum II. The possible excesses in the directions of Bootes II and Willman 1 are weaker with lower peak TS values ($\sim 7$). If interpreted as annihilation of dark matter particles into $\tau^+\tau^-$, the dark mass mass of $m_\chi \sim 14$ GeV and $\sim 80$ GeV are found for Bootes II and Willman 1, respectively. Much more data are needed to clarify whether these two potential signals are real and then reveal their origins.

Preparation and characterization of chitosan/zein film loaded with lemon essential oil: Effects on postharvest quality of mushroom (Agaricus bisporus)

In this study, different concentrations of lemon essential oils (LEO) were incorporated into chitosan/zein complex film (C/Z/L films) to improve its antioxidant and antimicrobial capacity, and the effects of C/Z/L films on mushroom quality were evaluated at 4 °C for 12 d. The antioxidant and antimicrobial activity of C/Z films were effectively improved by addition of LEO in a concentration-dependent manner. What's more, EAB value and gas permeability increased while TS value and water vapor permeability decreased upon the gradual increase of LEO content. During the entire storage, C/Z/L films were effective in suppressing PPO and POD activity of mushrooms as well as inhibiting the growth of microorganism. Mushrooms packaged with the film containing 6% LEO showed the lowest browning index and respiration rate. In addition, the C/Z/L film-treated mushrooms exhibited higher antioxidant capacity and more satisfactory texture properties. The results of our study presented that C/Z active film loaded with LEO could be used to maintain the postharvest quality of mushrooms.

Chitosan/Polyvinyl Alcohol/SiO2 Nanocomposite Films: Physicochemical and Structural Characterization

In the present study, the effects of the two ratios of polyvinyl alcohol /Chitosan (1:1 and 3:1) and nano-silicon dioxide (nano-SiO2) (0, 0.5, and 1%) on structural and physicochemical properties of PVA/Chitosan/ nano-SiO2 nanocomposite films were investigated. Our findings showed that the treatments' water solubility (WS) in the presence of nano-SiO2 and higher PVA content was decreased, and the lowest amount was in P3C1-1% (59%). The addition of silica nanoparticles decreased the water vapor permeability (WVP) of films, and the lowest amount of WVP was for treatment with a ratio of 1:1 of PVA/chitosan and 1% nano-SiO2 (P3C1-1%) which was 3.08× 10-10 g m s-1m-2 Pa. Tensile strength (Ts) value was achieved 35.86 MPa in higher PVA content and 1% of nano-SiO2 (P3C1-1%) which was the highest. However, the light transmission value of all treatments did not differ greatly. According to the FTIR results, the appropriate interaction between both polymers and nano-SiO2 was observed in the concentration of 1% nano-SiO2 in P1C1. Eventually, significant improvement of structural and physicochemical properties of the films could achieve in higher PVA content and concentration of 1% of nano-SiO2. Based on these results, these nanocomposite films could be considered suitable for the packaging sector and preserve food quality.